The rotary kiln is the middle part of a grate-kiln iron ore pelletizing process and consists of a large, cylindrical rotating oven with a burner in one end. The flame is the heart of the process, delivering the necessary heat. The combustion process is largely controlled by the turbulent diffusion mixing between the primary fuel jet and the combustion air, called the secondary air, which is mostly induced through the kiln hood. The relatively high momentum of the secondary air implies that the resulting flow field has a significant impact on the combustion process, justifying a systematic study of the factors influencing the dynamics of the secondary air flow field, by neglecting the primary fuel jet and the combustion. The objective of this work is thus to investigate how the geometry and the momentum flux ratio of the inlets affect the flow field in the kiln. Down-scaled models of the kiln are investigated numerically. It is found that the resulting flow field is highly affected by both the geometry and momentum flux ratio of the inlet flows, including effects from pressure driven secondary flow occurring in the semicircular inlet ducts. The dynamics of the flow is further investigated using proper orthogonal decomposition (POD) resulting in a deeper understanding of the forming, interaction and convection of the vortical structures.

References

References
1.
Petterson Reif
,
B. A.
, and
Andersson
,
H. I.
,
2002
, “
Prediction of Turbulence-Generated Secondary Mean Flow in a Square Duct
,”
Flow Turbul. Combust.
,
68
(
1
), pp.
41
61
.10.1023/A:1015611721026
2.
Westra
,
R.
,
Broersma
,
L.
,
van Andel
,
K.
, and
Kruyt
,
N.
,
2010
, “
PIV Measurements and CFD Computations of Secondary Flow in a Centrifugal Pump Impeller
,”
ASME J. Fluids Eng.
,
132
(
6
), p.
0611041
.10.1115/1.4001803
3.
Flack
,
R.
, and
Brun
,
K.
,
2005
, “
Fundamental Analysis of the Secondary Flows and Jet-Wake in a Torque Converter Pump—Part II: Flow in a Curved Stationary Passage and Combined Flows
,”
ASME J. Fluids Eng.
,
127
(
1
), pp.
75
82
.10.1115/1.1852486
4.
Liou
,
T.-M.
,
Chen
,
C.-C.
, and
Chen
,
M.-Y.
,
2003
, “
Rotating Effect on Fluid Flow in Two Smooth Ducts Connected by a 180-Degree Bend
,”
ASME J. Fluids Eng.
,
125
(
1
), pp.
138
148
.10.1115/1.1522413
5.
Kalpakli
,
A.
,
Örlü
,
R.
, and
Alfredsson
,
P. H.
,
2012
, “
Dean Vortices in Turbulent Flows: Rocking or Rolling?
,”
J. Visualization
,
15
(
1
), pp.
37
38
.10.1007/s12650-011-0108-8
6.
Demuren
,
A. O.
, and
Rodi
,
W.
,
1984
, “
Calculation of Turbulence-Driven Secondary Motion in Non-Circular Ducts
,”
J. Fluid Mech.
,
140
, pp.
189
222
.10.1017/S0022112084000574
7.
Fife
,
P. C.
,
1992
, “
Geometrical Aspects of Secondary Motion in Turbulent Duct Flow
,”
Theor. Comput. Fluid Dyn.
,
4
(
2
), pp.
51
70
.10.1007/BF00418235
8.
Demuren
,
A. O.
,
1991
, “
Calculation of Turbulence-Driven Secondary Motion in Ducts With Arbitrary Cross Section
,”
AIAA J.
,
29
(
4
), pp.
531
537
.10.2514/3.10616
9.
Raiesi
,
H.
,
Piomelli
,
U.
, and
Pollard
,
A.
,
2011
, “
Evaluation of Turbulence Models Using Direct Numerical and Large-Eddy Simulation Data
,”
ASME J. Fluids Eng.
,
133
(
2
), p.
021203
.10.1115/1.4003425
10.
Hurst
,
K. S.
, and
Rapley
,
C. W.
,
1991
, “
Turbulent Flow Measurements in a 30/60 Degree Right Triangular Duct
,”
Int. J. Heat Mass Transfer
,
34
(
3
), pp.
739
748
.10.1016/0017-9310(91)90121-T
11.
Larsson
,
I. A. S.
,
Lindmark
,
E. M.
,
Lundström
,
T. S.
, and
Nathan
,
G. J.
,
2011
, “
Secondary Flow in Semi-Circular Ducts
,”
ASME J. Fluids Eng.
,
133
(
10
), p.
101206
.10.1115/1.4004991
12.
Lai
,
Y. G.
,
So
,
R. M. C.
, and
Zhang
,
H. S.
,
1991
, “
Turbulence-Driven Secondary Flows in a Curved Pipe
,”
Theor. Comput. Fluid Dyn.
,
3
(
3
), pp.
163
180
.10.1007/BF00271800
13.
Hur
,
N.
,
Thangam
,
S.
, and
Speziale
,
C. G.
,
1990
, “
Numerical Study of Turbulent Secondary Flows in Curved Ducts
,”
ASME J. Fluids Eng.
,
112
(
2
), pp.
205
211
.10.1115/1.2909389
14.
Moles
,
D. F.
,
Watson
,
D.
, and
Lain
,
P. B.
,
1973
, “
The Aerodynamics of the Rotary Cement Kiln
,”
J. Inst. Fuel
,
46
, pp.
353
362
.
15.
Morton
,
C.
, and
Yarusevych
,
S.
,
2014
, “
Vortex Dynamics in the Turbulent Wake of a Single Step Cylinder
,”
ASME J. Fluids Eng.
,
136
(
3
), p.
031204
.10.1115/1.4026196
16.
Younis
,
B. A.
, and
Abrishamchi
,
A.
,
2014
, “
Three-Dimensional Turbulent Vortex Shedding From a Surface-Mounted Square Cylinder: Predictions With Large-Eddy Simulations and URANS
,”
ASME J. Fluids Eng.
,
136
(
6
), p.
060907
.10.1115/1.4025254
17.
McClean
,
J. F.
, and
Sumner
,
D. D.
,
2014
, “
An Experimental Investigation of Aspect Ratio and Incidence Angle Effects for the Flow Around Surface-Mounted Finite-Height Square Prisms
,”
ASME J. Fluids Eng.
,
136
(
8
), p.
081206
.10.1115/1.4027138
18.
Wilkins
,
S. J.
,
Hogan
,
J. D.
, and
Hall
,
J. W.
,
2013
, “
Vortex Shedding in a Tandem Circular Cylinder System With a Yawed Downstream Cylinder
,”
ASME J. Fluids Eng.
,
135
(
7
), p.
071202
.10.1115/1.4023949
19.
Larsson
,
I. A. S.
,
Granström
,
B. R.
,
Lundström
,
T. S.
, and
Marjavaara
,
B. D.
,
2012
, “
PIV Analysis of Merging Flow in a Simplified Model of a Rotary Kiln
,”
Exp. Fluids
,
53
(
2
), pp.
545
560
.10.1007/s00348-012-1309-1
20.
Larsson
,
I. A. S.
,
Lindmark
,
E. M.
,
Lundström
,
T. S.
,
Marjavaara
,
B. D.
, and
Töyrä
,
S.
,
2012
, “
Visualization of Merging Flow by Usage of PIV and CFD With Application to Grate-Kiln Induration Machines
,”
J. App. Fluid Mech.
,
5
(
4
), pp.
81
89
.
21.
Granström
,
R.
,
2012
, “
Modeling the Aerodynamics of Iron Ore Pelletizing Kilns
,” Licentiate thesis, Luleå University of Technology, Luleå, Sweden.
22.
Burström
,
P.
,
Lundström
,
S.
,
Marjavaara
,
D.
, and
Töyrä
,
S.
,
2010
, “
CFD-Modeling of Selective Non-Catalytic Reduction of NOx in Grate-Kiln Plants
,”
Progr. Comput. Fluid Dyn. Int. J.
,
10
(
5/6
), pp.
284
291
.10.1504/PCFD.2010.035361
23.
Larsson
,
I. A. S.
,
Lundström
,
T. S.
, and
Marjavaara
,
B. D.
,
2015
, “
Calculation of Kiln Aerodynamics With Two RANS Turbulence Models and by DDES
,”
Flow Turbul. Combust.
94
(
4
), pp.
859
878
.10.1007/s10494-015-9602-8
24.
Menter
,
F. R.
,
Kuntz
,
M.
, and
Langtry
,
R.
,
2003
, “
Ten Years of Experience With the SST Turbulence Model
,”
Turbulence, Heat and Mass Transfer 4
,
K.
Hanjalic
,
Y.
Nagano
, and
M.
Tummers
, eds.,
Begell House
,
Redding, CT
, pp.
625
632
.
25.
Menter
,
F. R.
,
1994
, “
Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications
,”
AIAA J.
,
32
(
8
), pp.
1598
1605
.10.2514/3.12149
26.
Strelets
,
M.
,
2001
, “
Detached Eddy Simulation of Massively Separated Flows
,”
AIAA
Paper No. 2001-0879.10.2514/6.2001-879
27.
Menter
,
F. R.
, and
Kuntz
,
M.
,
2003
, “
Development and Application of a Zonal DES Turbulence Model for CFX-5
,” Ansys, CFX-Validation Report, Technical Report No. CFX-VAL17/0503.
28.
Ansys CFX
,
2012
,
Ansys CFX-Solver Theory Guide
,
Release 14.5, Ansys
,
Canonsburg, PA
.
29.
Sciberras
,
M. A.
, and
Coleman
,
G. N.
,
2007
, “
Testing of Reynolds-Stress-Transport Closures by Comparison With DNS of an Idealized Adverse-Pressure-Gradient Boundary Layer
,”
Eur. J. Mech. B Fluids
,
26
, pp.
551
582
.10.1016/j.euromechflu.2006.11.001
30.
Celik
,
I.
,
Ghia
,
U.
,
Roache
,
P.
, and
Freitas
,
C.
,
2008
, “
Procedure for Estimation and Reporting of Uncertainty Due to Discretization in CFD
,”
ASME J. Fluids Eng.
,
130
(
7
), pp.
338
344
.10.1115/1.2960953
31.
Ferziger
,
J. H.
, and
Peric
,
M.
,
2002
,
Computational Methods for Fluid Dynamics
,
3rd ed.
,
Springer
,
Berlin
.10.1007/978-3-642-56026-2
32.
Hunt
,
J. C. R.
,
Wray
,
A. A.
, and
Moin
,
P.
,
1988
, “
Eddies, Stream, and Convergence Zones in Turbulent Flows
,” Center for Turbulence Research, Standford University and NASA, Technical Report No. CTR-S88.
33.
Meyer
,
K. E.
,
Pedersen
,
J. M.
, and
Özcan
,
O.
,
2007
, “
A Turbulent Jet in Crossflow Analysed With Proper Orthogonal Decomposition
,”
J. Fluid Mech.
,
583
, pp.
199
227
.10.1017/S0022112007006143
34.
Yuan
,
L. L.
,
Street
,
R. L.
, and
Ferziger
,
J. H.
,
1999
, “
Large-Eddy Simulations of a Round Jet in Crossflow
,”
J. Fluid Mech.
,
379
, pp.
71
104
.10.1017/S0022112098003346
35.
Merzari
,
E.
,
Pointer
,
W. D.
, and
Fischer
,
P.
,
2013
, “
Numerical Simulation and Proper Orthogonal Decomposition of the Flow in a Counter-Flow T-Junction
,”
ASME J. Fluids Eng.
,
135
(
9
), p.
091304
.10.1115/1.4024059
36.
Wen
,
Q.
,
Kim
,
H. D.
,
Liu
,
Y. Z.
, and
Kim
,
K. C.
,
2014
, “
Structure Analysis of a Low Reynolds Number Turbulent Submerged Jet Interacting With a Free Surface
,”
ASME J. Fluids Eng.
,
136
(
10
), p.
101104
.10.1115/1.4027620
37.
Berkooz
,
G.
,
Holmes
,
P.
, and
Lumley
,
J.
,
1993
, “
The Proper Orthogonal Decomposition in the Analysis of Turbulent Flows
,”
Annu. Rev. Fluid Mech.
,
25
(
1
), pp.
539
575
.10.1146/annurev.fl.25.010193.002543
38.
Durgesh
,
V.
, and
Naughton
,
J. W.
,
1993
, “
Multi-Time-Delay LSE-POD Complementary Approach Applied to Unsteady High-Reynolds-Number Near Wake Flow
,”
Exp. Fluids
,
49
(
3
), pp.
571
583
.10.1007/s00348-010-0821-4
You do not currently have access to this content.